The present invention relates to an inflator used in an airbag apparatus, and in particular, to a hybrid inflator for releasing a gas generated from a gas-generating chemical and a pressurized gas stored therein. In addition, the present invention relates to an airbag apparatus using the inflator.
A hybrid inflator includes a gas generator containing gas-generating chemicals ignited by an initiator; and a tank charged with a pressurized gas. When the chemicals start to react by the initiator, the reaction gas flows into the tank. Then, a sealing plate separating the tank and a gas outlet is ruptured, and a mixed gas of a gas stored in the tank (hereinafter referred to as stored gas) and the reaction gas is released from the gas outlet.
Japanese Patent Publication (Kokai) No. 2003-81050 discloses an inflator in which one end of a cylindrical tank is attached to a gas generator by welding, and a gas outlet is provided at the other end of a gas storage chamber.
In the inflator disclosed in Japanese Patent Publication (Kokai) No. 2003-81050, a distance from a welded part of the tank and the gas generator to the chemicals in the gas generator is short. Therefore, it is necessary to perform a welding so as not to ignite the chemicals due to heat generated during the welding. Accordingly, it is difficult to produce the inflator and reduce manufacturing cost of the inflator.
In Japanese Patent Publication (Kokai) No. 2003-81050, the opening at one end of the tank is welded directly to the gas generator, and the gas is charged in the tank after the welding between the tank and the gas generator is completed. When the gas is charged after the tank and the gas generator are welded, it is necessary to provide a gas-charging device in an assembling process of the inflator, thereby increasing assembling cost of the inflator.
In view of the problems described above, an object of the present invention is to provide an inflator that is easy to manufacture.
Another object of the present invention is to provide an inflator that is constructed by attaching a tank filled with a gas in advance to a gas generator.
Further objects and advantages of the invention will be apparent from the following description of the invention.